Telephone



-w.'s. TURNEY .ET AL TELEPHONE May 14, 1929.

Filed 1 813.8, 1926 V/QW patented May 14, 1929.

UNITED STATES uann PATENT OFFICE.

JJIEILLA'QNT. S. TUB-HEY, OF CONROE, TEXAS, AND ALBERT IN. LONG, 31%., OF GREENSB'URG, PENNSYLVANIA; SAID LONG ASSIGNOR TO SAID TURNEY.

TELEPHONE.

Application filed February 8, 1926.

The present invention relates to electromagnetic telephones, and more particularly clectroanagnetic reproducing devices of the hind commonly employed for radio pur poses, although it not limited to use in connection with radio. The invention more especially adaptable to the so-called loud speaker units where the current values are relatively high, but is also applicable to the usual type of ear phone.

In the ordinary telephone, there is but a single winding of wire on the magnetic pole piece, and this winding is usually connected in a direct current circuit. Since it is in a direct current circuit, the arn'iature or diaphragm is attracted or biased as long as the receiver is in. the circuit. constant attraction of the armature or diaphragni is not desirable because it interferes with the normal vibration. of the arn'iature or diaphragm in response to the current variations passing through the winding.

It the usual receiver is connected in an alternating current circuit rather than in. a

direct current circuit, it does not function.

to the best advantage because the windings,

which are arranged for direct current, are

not suitable for alternating current impulses.

According to the present invention, it is proposed to provide a receiver having specially arranged windings on the pole pieces particularly adaptable for use in alternating current circuits. A. furtherobject of the present invention is to provide, in combination with aradio or other circuit, a receiver especially adapted. to respond to alternating current in'ipulses, and to provide a circuit wherein the receiver is energized by alternating currents and protected against direct.

llhis biasing or Serial No. 86,814.

closed in Figure 1 with the diaphragm oi. the receiver removed;

Figure 3 is a diagrammatic view illustrating another arrangement of windings on the pole pieces of a receiver; and

Figure t illustrates a radio or tllcll'ifllollhj tube circuit having an alternating current receiver connected therewith.

Referring to the construction shown in Figures 1 and 2 of the drawings, 2 designates a casing of any suitable constructiol'i, 3 is the diaphragm or armature oi" the reproducer, and 4t designates a cap which closes the casing and retains the armature in place. This arrangement is similar to the common telephone receiver, but it will be apparent that the invention is not limited to this par- "icular arrangement of armature and casing.

ithin the casing are pole pieces 5 and 6 arranged in the usual manner. The pole piece 5 is provided with two separate windings 7 and 8. The winding 7 is at one end of the pole piece, and the winding 8 is preferably at the other end oi? the pole. piece. The turns of wire in the winding 8 are reversed. to those in the winding 7.

On the pole piece 6 are also two windings 7 and 8 arranged sin'iilarly to the windings on the pole piece 5, but on reverse ends of the pole piece with respect to the windings on pole piece In other words, the winding 7 which corresponds with the winding 7 iii.

the direction in which it wound is at the lower end of the pole piece 6 in Figure 1, while the winding 7 on the pole piece 5 is at the .1111201. end. The windings 8 and 8 are, oil course, correspondiugly staggered. 'lho inner ends of? the coils 7 and 7 are connected by a cross wire 9, and the inner ends of the windings 8 and. r are connected by a cross connection 10. The input terminals tor the receiver are designated 11 and 12 respectively. The coils 7 and. 8 are connected through a wire 18. By this arrangement of connections the windings 7 and 7 are in series, and the windings 8 and 8 are in series, while both sets of windings are continuously in series with each other.

As thus arranged, the receiver will operate most eiifectively on alternating currents. The windings 7 and 8 being reversed. to each other in the direction of their windings but being on opposite sides of the alternating current supply wires, will tend to inagne'tize net-ism induced in the core 5.

the pole piece 5. In like manner, the windings 7" and 8' will operate together to magnetize the pole piece 6. At the same time, by the staggered arrangement of the coils the pole piece 6 will havea magnetism induced therein of a polarity opposite to the magv This will mean that there will be the desired opposite polarity at the ends of the pole pieces directly beneath the armature.

' In the modification shown in Figure 3, a somewhat similar arrangement is employed. In this view, 14 and 15 designate associated cores or pole pieces. 1 lVound about the core 14 are coils 16 and 17. lVound about the core 15 are windings 1G and 17. The inner ends of the windings 16 and 16 are connected by across wire 18. One end of the winding 17 is connected through a diagonal cross wire 19 with the opposite end of the winding 16. One end of the winding 17 is connected through a diagonally extending cross wire 20 with the opposite end of the winding 17.

The windings as thus disposed will tend to produce the desired magnetic polarity in the pole pieces 14 and 15 when the terminals 21 and 22 are connect-ed in an alternating current circuit. 7

One manner of using a phone embodying the present invention is illustrated in Figure 4. In this figure, which is merely diagrammatic, 23 indicates a thermonic tube, which may be the last tube in a radio receiving apparatus. The thermionic tube 23 is the usual output circuit'including the plate lead 24, the B battery and the return lead 26. Connected in series with the plate lead 24 and the plate current source 25 is a choke coil 27. The receiver is designated 28 and is coupled in a shunt circuit across the choke [coil and source o1 plate current 25, the shunt rent impulses and which serves to bypass alternating current impulses generated in the shunt circuit by reason of the direct current variations in the plate or output circuit of the thermionic tube 23,

As thus arranged it will be seen that the telephone 28 responds only to alternating currents and that it is not biased by any direct current circuit, At the same time, the

phone circuit is inductively coupled into the output circuit of the tube whereby alternating current impulses will be impressed. on the terminals of the telephone in exact accordance with the variations in the flow ol current in the plate circuit of the thermionic tube.

The advantages of: the present invention arise out of the fact that the wiiulings are so arranged about the pole pieces that the phone will respond most effectively to alternating currents, and alternating currents can be more elliciently used in the receiver than they can in the ordinary type of receiver arranged primarily for use in direct current circuits only.

A further advantage of the invention arises out of the fact that an arrangement is provided for using an alternating current telephone receiver in an alternating current circuit without any direct current potentials being impressed thereon.

lVe claim:

1. In a telephone, a pair of pole pieces, and a pair of windings on each pole piece, one winding on each pole having an end leading to an input terminal, the other two windings having an end which is connected together, the remaining ends of corresponding windings being connected by cross-over wires.

2. In a telephone, a pair of pole pieces, a

pair of windings on each pole piece with the turns thereof in opposite directions, the windings of similar direction on the two pole pieces being connected together, the two windings of like direction thereby being connected in series, the two groups of windings also being connected in series. '7

In a telephone, a pair of pole pieces, a pair of windings on each pole piece, the windings on each pole piece being disposed at opposite ends thereof, one of the windings on each pole piece being reversed. to the winding on the other, the windings being reversel arranged on the two pole pieces, the windings of like direction being connected together, and all of the windings being connected in series.

In testimony whereof we have hereunto set our hands.

WILLIAM S. TURN EY. ALBERT N. LONG, JR. 

